14 test screens
Solid colours for dead and stuck pixels, plus gradients, a fine checkerboard, a grid and a dark screen for uniformity.
Free · Full screen · Any monitor, laptop or phone
Dead Pixel Test: Check Your Screen in Seconds
Find dead, stuck and hot pixels with full-screen colour tests. Then check banding, uniformity and backlight bleed, see your real resolution and refresh rate, and try the stuck pixel fixer. Everything runs in your browser.
- 14 test screens
- Refresh rate in Hz
- HDR and colour gamut check
- Stuck pixel fixer
Click, tap or press Space or → for the next screen, ← to go back, Esc to exit. Clean your screen first so dust is not mistaken for a pixel.
Or jump to a test screen
Your screen
- Screen size
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- Physical pixels
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- Browser window
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- Pixel ratio
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- Refresh rate
- Measuring…
- Colour depth
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- Colour gamut
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- HDR
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- Touch screen
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Stuck pixel fixer
Flashing light warning. The fixer flashes rapidly changing colours. Do not use it if you are sensitive to flashing lights or have photosensitive epilepsy, and do not look at it directly.
Black 1 / 14
Why it is different
Why this dead pixel test is better
Most dead pixel tests only cycle a few colours. This one checks your whole display, from single pixels to backlight and refresh rate.
Refresh rate check
Measures how many frames per second your screen actually shows, so you can confirm a 60, 120, 144 or 240 Hz monitor.
HDR and colour gamut
See if your browser reports HDR and wide colour (P3 or Rec. 2020), along with resolution, pixel ratio and colour depth.
Stuck pixel fixer
Rapidly changing colours can sometimes revive a stuck pixel. Use a small box over the pixel or the full screen.
Banding and bleed tests
Smooth gradients reveal colour banding, and the dark screen shows backlight bleed and IPS glow at the edges.
Works on any screen
Test monitors, laptops, TVs with a browser, tablets and phones. Tap to move to the next screen on touch devices.
How to use
How to test your screen for dead pixels
A careful check takes two to three minutes.
Clean the screen
Wipe the display with a dry microfibre cloth so dust is not mistaken for a pixel.
Go full screen
Press Start full-screen test. Dim the room lights a little for the dark screens.
Scan each colour
Look slowly across the whole screen on each colour. Move closer and check the corners and edges too.
Note what you find
A dot that never changes is a dead or hot pixel. A dot stuck on one colour is a stuck pixel, which the fixer may help.
Explained
Dead, stuck and hot pixels explained
Each pixel has red, green and blue sub-pixels. The colour a faulty pixel shows tells you what went wrong.
| Type | What you see | Can it be fixed? |
|---|---|---|
| Dead pixel | A black dot on white and bright colours | Rarely. It usually needs a warranty repair. |
| Stuck pixel | A red, green, blue or other coloured dot that stays the same | Sometimes. Try the stuck pixel fixer. |
| Hot pixel | A white dot that stays lit on black | Rarely. Check your warranty. |
| Dust or smudge | A soft grey spot that may move when you clean | Yes. Clean the screen gently. |
Backlight bleed and IPS glow
On the dark screen, light leaking from the edges is backlight bleed. A glow that changes when you move your head is IPS glow. Small amounts are normal on LCD screens, but bright patches visible in normal use may be covered by warranty.
What to do if you find one
- Take a photo of the pixel on the colour where it is clearest.
- Check the return window. New screens are often easier to swap within the store's return period.
- Read the pixel policy. Many makers only replace a screen after a set number of faulty pixels.
- Try the fixer for stuck pixels before you send it back.
FAQ
Dead pixel test FAQs
How do I check my screen for dead pixels?
Press Start full-screen test and look carefully across the screen on each colour. Dead pixels show as black dots on bright colours, and stuck pixels show one colour that never changes.
What is the difference between a dead and a stuck pixel?
A dead pixel stays black because it gets no power. A stuck pixel stays lit in one colour, such as red, green or blue. Stuck pixels can sometimes be fixed, while dead pixels usually cannot.
Can the stuck pixel fixer really work?
It helps in some cases. Place the flashing box over the stuck pixel and let it run for 10 to 20 minutes. If the pixel is still stuck after a few tries, it is probably a hardware fault.
Is the stuck pixel fixer safe?
It is safe for your screen, but it flashes rapidly. Do not use it if you are sensitive to flashing lights or have photosensitive epilepsy, and avoid looking at it directly while it runs.
How do I check my monitor refresh rate?
The Refresh rate field measures your screen automatically. If it shows 60 Hz on a 144 Hz monitor, set the higher rate in your display settings and use a cable that supports it, such as DisplayPort.
Can I test my phone or TV screen?
Yes. Open this page on the device, start the test and tap to move through the screens. On iPhone, the test fills the browser window, so turn the phone sideways for the best view.
How many dead pixels are acceptable?
It depends on the maker's pixel policy. Some brands offer a zero dead pixel guarantee, while others only replace a screen after several faulty pixels. Check your warranty terms.
What does the gradient test show?
A smooth gradient should blend evenly. Visible stripes or steps are called banding, which can come from low colour depth, heavy compression or aggressive display settings.
Test your screen now
Go full screen, cycle through 14 test patterns and see your real refresh rate. Free and works on any display.
Open the dead pixel test